Low water alarm



Sept. 30, 1952 H. A. BOHUSLAV LOW WATER ALARM Filed Dec. 6, 1.948

55 INTERRUPTERJ 5| THERMOSTATIE SWITCH '5 COEJLING LIQUID T0 PRIME MOVER A f/m/s F7. BOHUSLHV,

IN V EN TOR.

BY Maw QTTOQNEVS Patented Sept. 30, 1952 UNITED STATES PATENT OFFICE;

LOW WATER ALARM- Ha s A- hu a L ssies po ties-enigma t E ne n Go t o nc," v has, Angeles;, Qa it a corpo at of Qa rifprn a Application December 6, 1948, Serial No.6'3 0 1 1-G aims- 1 v Thisinvention relates-tocontrol devices.v

A main object of the present invention is. to provide newand useful improvements, in control devices; for indicating low;- water; and excess pressureconditions'. I e

A main object of; the present invention is to provide a control device for a chamber containins-.- wate and am. th t i imple and ne pensive and which will indicate not only when thereis a lowwater condition within the chamber but will also indicate increases in pressure within the chamber,

Another main object of the present invention is topprovide acontrol device for a chamber con.- taining water and steam which control device provides anunobstrncted passage from the liquid in the chamber to the air outside the chamber and in which a thermal responsive control means is positioned directly in the path of flow of fluid through thepassageway.

Another main object of the present invention is. to provide a control devicewhich provides an airtight subchamber extending outwardly from the, chamber below the water level thereinand which controldevice is actuatable when the water within the chamber falls below thevsubchamber. I Another objectof the present invention is to provide a system including a control device as-. sociated with a vapor phase unit which vapor phase'unit is used to cool the cooling water of a prime mover, and in which system the control device is adapted to turn off the prime mover when there-is a low water condition in the cham- 1361;

Another object is to provide a system as above setout wherein the control device will turn offthe prime mover when there is an excess steam within the vapor phase unit or when there is an excess pressure within thevaporphase unit.

With the foregoing and other objects in View, which will be made manifest in the following detailed description and specifically pointed'out in the appended claims, reference is had to the acccmpanying; drawings for an illustrativeembodiment of'the invention, wherein:

Fig. 1 discloses a sectional elevation view-of a vapor'phase unit with the control device associated with the condenser of the vapor phase unit; I

Rig. 2-;;disclos.es a vapor phase unit with the control device-directlyassociatedwith the bodyof liquid within the vapor phase unit; and

systems, and

Fig.3 discloses a vapor phase unit in which the; control. device is directly associatedwith the s. o: e undetec ed; that the nresent where n simil -.r ;e enc characters. desi nate m la n tsthroush ut, vari us embodl an es; the present invention are disclosed and are own a asso ia ed W hin por hese unitne tho sh it n. has be n a a ted..- ort e. va orv l a A sw-i e c ibed: that the inve ion; not l ldfi to b li i ,v a: aDQ Y hase 5 3 Q5 e vent on ll end: i e t oth svsteies uc as iler nd. the; ike

One form of the vapor phase nnit lS jSllGVEIA-h} F 1 d hi v 99 Pha e 111 i5 U $4 3 us h omes rtof rimemo er iqrvins an e sud-.1 5 a di e n ne soline 1 21 61 194 comhus: tion n inea naturalsas; engine or aturbine orvarious other: devices in which coelingtliq mu tsu lied 2 a prime -mo he rev n ha t m, the co insi uld s. c n e e r en me m er tome v por nha e stem at approximately boiling temperature and in the vapor phase system the-liquid may be immedi te v ex e le o d wn fr m he a our phase unit and used over again while the vapor; passes to a; condenser wherei-t-is condensed and the. liquid condensed from the vapor is returned to the liquidibody withinthe vapor phase unit; It, can beseen then thatthe vaporpressure with;

Y suc a te s-sli t abov mo nh rie as. contra ed tea s e m. boiler: t m he the pre su e. mm he v. poun s e quare-in rhlooieoundspe u r inc o r n- The va mt Pha ni disc se in Fi oom 1 prises a chamber l 0-,adapted.tO contain avolume of liquid tl whichliqnid isconveyed to thecham -r ber- ID, by aconduit 12 from a prime mover-not shown and the liquid II is conveyedaway from chamber lllby conduit l3. Thepipe l-2--i-n-some vaporphase systems conveysythev cooling liquid intothe chamber In tangentially ofthecham: hen so that the liquid-whirls about within cham ber Uland'forms a liquidsunface I4, asishow nvin There is generally some sort or shielding=means l=5-inth e:bo,ttom ot the chamber H] to provide a quiescent zone and there-may beaaniextension' on the. conduit 13 extending upwardlywwithin chamber In so that any-impurities, mudvor tlie likewi'll be; collected around: the portion l1 and will not .be. returned to thet-prime mover:

There is. a. pluralityzof shields 20 and- 21i pro; vided within chamber lfl'to'serve as; a separator-- J for the liquid-vapor mixture thatrises'l-ipwardli 3 through shield 26 and around shield 2|. There is a drain pipe 22 leading from shield 28 down into chamber below the liquid level therein so as to be sealed by the liquid. The steam condensing within shield 20 will therefore flow down drain 22 into chamber ID.

A condenser generally entitled 24 is usually mounted'above the liquid vapor chamber l0 and may be mounted on the top of chamber l0 and has a header 25 communicating with chamber H) as shown in Fig. 1 and there is a second header 28 which has a liquid return pipe or conduit 28 leading therefrom which conduit leads down below the liquid level in the chamber H) a point somewhere near the low water mark of the chamber. There are a plurality of conduits 36 leading from header 25 to header 26 and these conduits may have fins 3| provided thereon and there is some sort of means such as a fan 33 for drawing air by or over the conduits 38.

The vapor rising up in header 25 will be condensed and it flows through conduits 30 and the liquid condensed from the vapor will flow down through header 26, conduit 28 and back to chamber l8. r

In the control set 'up as shown in Fig. 1 the control device is connected to the header 26 preferably at the upper part thereof and comprise a conduit 36 which leads outwardly from header 26 and which condu t has a thermal responsive means 3'! mounted thereon with the lower portion of the thermal responsive means depending down within conduit 36.

g The thermal responsive means 31 may be of anyof the usual types such as a bi-metallic strip, or a low melting point mass of metal which is heated when contacted by steam to release a contact and either to make or break a circuit.

Instead of the, thermal responsive means 3! there may be an audible means such as a whistle ingelrted in the place of thermal responsive means It is preferable that the thermal responsive means 81 be connected to the prime mover so as to'cut off or turn off the prime mover whenever the thermal responsive means is actuated. Vapor phase units are widely used with prime movers in "localities where constant attention to the prime movers is not possible nor desirable and, therefore, these prime movers operate without attention and therefore the present invention provides some means for automatically cutting off the prime; mover if the water level within chamber |0 should fall below a predetermined low level and the control device will also operate whenever an excess load is applied to the prime mover or whenever the fan belt breaks on the prime mover or when any other event occurs which causes excess heating of the fluid The operation of the device disclosed in Fig. l is as follows. In'such a system as described there is'generally a constant volume of liquid in the cooling circuit and should this constant volume be decreased by leaks or other causes so that the water level 14, shown in Fig. 1, drops below the lower end of conduit 28, then the steam or vapor within chamber I0 will exit through conduit 28 out through conduit 36 and thereby heat thermal responsive means 31 which in turn will cut off the prime mover. The thermal'responsive means 31 will not be actuated by the vapor'rising up into header 25 because this vapor is cooled and condensed bypassing through conduits 30 and so that there is only liquid within header 26 or '4 possibly some air which can escape through conduit 36.

If, on the other hand, there is overheating of the cooling liquid above the capacity of the condenser 30 and so that an excess pressure is created within chamber l0 then the steam or vapor will not all be condensed within conduits 30 and will then pass into header 26 and out through conduit 36 contacting thermal responsive means 31 and actuating thermal responsive means to cut off the prime mover.

It will be seen then that the control device in Fig. 1 is adapted to be actuated by low liquid level conditions and also by excess pressure or excess steam conditions.

In Fig. 2, the chamber 48 is a chamber such as chamber l0 and there is a conduit 4| oommunicating with the liquid space within chamber 48 and this conduit 4| extends outwardly from the chamber 46 and then upwardly above the water level 43 in chamber 40 and exits at 45. Conduit 4| may have fins 46 on the vertical part thereof as shown in Fig. 2.

There is a thermal responsive means 48 provided in the upper end of conduit 4| which thermal res onsive means extends downwardly so as to be directly in the path of flow of any fluid which passes through conduit 4|.

In both the set ups shown in Figs. 1 and 2 there is an unobstructed passage from the liquid space in the chamber to the air outside the chamber so that there is permanent communication between the liquid space and the air.

The device in Fig. 2 operates as follows.

Whenever the water level therein falls to a point such as 49 the vapor or steam within chamber 40 may then pass out of chamber 40 and through the conduit 4| and out through 45 and in doing so will flow over and around the thermal responsive means 48 to heat up the thermal responsive means which will be actuated. to cut off the prime mover.

The device as shown in Fig. 2 will not be actuated under ordinary conditions since the water in conduit 4| will only rise to a point substantially even with the liquid level 43 within chamber 40 and the rest of conduit 4| will not have air therein which forms an insulating medium between the thermal responsive means 48 and the water or liquid within the lower part of conduit 4|.

The device shown in Fig. 2 will also function as an excess pressure device since whenever the pressure within chamber 48 increases to an extent such that Water or liquid is forced out through conduit 4| up through the vertical part of conduit 4| and out through the portion 45 then this liquid will'be in contact with the thermal responsive means 48 and will actuate the thermal responsive means 48 to turn off or cut off the prime mover.

By positioning the thermal responsive means 48 directly in the path of flow of any fluid which passes through conduit 4| a quicker and more reliable response by the thermal responsive means 48 are insured.

It will be appreciated that by the present in-" vention all floats or valve members or moving parts or the like have been eliminated and a reliable and simple control device has beenv provided to guard against low water conditions and excess pressure conditions.

In the device in Fig. 3 there is control chamber 5| of similar construction to control chamber aerate? 11.9 iuherein'there-isa conduitiizpmr dinaaasu chamber extending 'outiiin ahorizontal direction jtrom, chamher filgandii this'case theaoutersend ohconduit 53: is. sealed by :a .plug' 54: or other suitable: means so: that, an airtight subchamber'zis provided-for-chambeuil; .v It. is: important that the conduit 53v be hori-. zontal for if it. were" tilted upwardly there would be a; good likelihood thatz airwould be trapped within the conduit 53- which would insulate the thermal responsive means i 5 5 and therefore re- 'sulting' in'very' unreliable operation of the system. However, since theiconduit 531s ina'horizontal position the liquid within: chamber il'willflow intoand completely fill the conduit; 53. .Cooling fins. 51 are provided. on conduit53 and; therefore, there w-ill be-a temperature differential.be-s tween the liquidat the outer end of the conduit and theliquid within; chamber 51' and thistemq perature' diflerential'is sufiicie'nt so that the tam--v perature responsive means 55 will notbe actuated when-the liquid level'is normal. However, when the liquid level falls down' below conduit 53- the liquid within conduit 53 will flow into chamber 5.! and the vapor: within chamber 5| will then flow into conduiti 53 i contacting thermal responsive :means 55 and causi-ng'the thermal responsive means to beactuated toturn off'orcut ofi-theprimemoverc .In some prior control devices the arrangement a has been such'that vapor, orair was trapped in e v c y o eth rm l respo sive meansand so the thermal responsive means was not exposed directly to the flow of 'fluid through any conduit such as: is-the situation in the present invention. These air or vaportraps result i i-very undesirable, and unreliable operation which, the present invention overcomes,

1V arious changes may bev made in the details of oonstructioriv without departing from the spirit and-scope.- of; the inventionas defined bytheappen ed a m r 7'12 c im;

1. A low liquid control device for a chamber containing liquid and vapor, comprising a conduit communicating with the chamber at approximately the low liquid mark therein, the conduit extending upwardly above the liquid level and outwardly from the chamber and being permanently open to the air at its upper end, and thermal responsive means adjacent the upper end of the conduit adapted to be actuated whenever the liquid in the chamber falls below the conduit and permits the vapor to pass through the conduit and contact the thermal responsive means.

2. In a system of the character described in which water at substantially boiling temperatures is circulated through the cooling jacket of a prime mover and through a steam-separating chamber having normally therein a liquid zone and a steam zone, the improvement which resides in providing a conduit having one of its ends in communication with the water zoneand the other one of its ends in communication with thermostaticallyoperated means, said thermostatically-operated means being operated upon presence of steam in the conduit, said thermostatically-operated means comprising an electric switch connected to control the operation of said prime mover, said conduit extending outwardly from the chamber in substantially a horizontal direction and having the end thereof permanently sealed to provide an air-tight subchamber, said thermostaticallyoperated means being disposed adjacent the end of the conduit and being actuated whenever the liquid. the .cnamber lfalls; ;a.eminent-amount tonallow steaml tolenter the conduit andoqntaet I and a steam zone, the improvementwhichree sides in providing a conduit-having one of itsends in communication with the waterzone and the other one of its ends in communication with thermostaticallywperated means, said thermostaticallyeoperatedmeans 'being; operated upon.

presence of steam in the conduit, said,thermos statically-operated means comprising anelectric switch connectedto control the operation of said prime mover, said conduit providing-anair-tighthorizontal subchamber-which extends outwardly from the liquid zone and below theliquid'level therein, said thermostatically-operated 'means disposedadjacent the outer end of the "subc-hame ber and'being actuated whenever the liquid in the water zone falls a sufficient-amount tel-allow the steam to enterthe conduit and contact the thermal-responsive means.-

4. A low liquid control device-for a chamberat its upper end, and thermal responsive controlmeans adjacent the upper endof' the conduit adapted to be actuated wheneverthelliqui'd"in the. chamber falls belowthe lower endoi thecon:-v duit and permitsthe vapor to pass through the. on nd onta t theth rmalr pon iva an: trolmeans.

5; A low liquid control device for achamber containing, liquid and, vapor, comprising a con.-

l t Comm icating with the chamber below the liquid" level therein, the conduit extending upl-l war-dly to a level above the liquid level in the chamber and out from the chamber, said conduit providing an unobstructed passageway from the chamber below the liquid level therein to the air and being permanently open to the air, and control means adjacent the upper end of the conduit responsive to the heat of the vapor and adapted to be actuated by the vapor whenever the liquid in the chamber falls below the lower end of the conduit and permits the vapor to pass through the conduit and contact the control means.

6. A low liquid control device for a chamber containing liquid and steam, comprising means providing a passageway communicating with the liquid in the chamber below the surface thereof and leading upwardly above the liquid level and communicating with the air, said passageway being unobstructed throughout its length to provide permanent communication between the liquid body and the air, and control means adjacent the upper end of the passageway responsive to the heat of the vapor and adapted to be actuated by the vapor whenever the liquid in the chamber falls below the lower end of the passageway and permits the vapor to pass through the passageway and contact the control means.

7. In combination with a water cooled prime mover, a vapor phase unit for cooling the water used to cool the prime mover, the vapor phase unit including a chamber containing liquid and 7 vapor, means providing a passageway communieating with the'liquidin the chamber below the surface thereof and leading upwardlyabove the liquid level and communicating with the air, and controlmeans adjacent the upper end of the passageway responsive to theheat of the vapor to turn the prime mover ofi; said control means,

adapted-to be actuated by the vapor whenever the liquid in the chamber falls below the lower end of the passageway and permits the vapor to pass through the passageway and contact the control means.

8-. In combination as set out in claim 7 in which the passageway is unobstructed throughout to provide permanent communication between the liquid body and the air.

'9. A device as set out in claim 6 in which the control means is positioned in the passageway so as to be directly subjected to the flow of vapor through the passageway. 10. A device as set out in claim 6 in which the control means is positioned in the passageway so as to be directly in the path of vapor flowing through the passageway.

11. A low water and excess pressure control device for a chamber containing liquid and vapor, comprising means providing a passageway communicating with the liquid in the chamber below the surface thereofand leading upwardly above the liquid level and communicating with the air, said passageway being unobstructed throughout its length to provide permanent communication of the liquid body and the air, and control means adjacent the upper end of the passageway responsive to the heat of the vapor or liquid andadapted to operate as a low liquid control whenever the liquid in the chamberfalls below the lower end of the passageway and permits the vapor to pass through the passageway and contact the control means, said control means actuating as an excess pressure control device whenever the pressure in the chamber increases an extent such as to cause fluid to contact the control means.

12. In a system of thechar'acter described in which water at substantially boiling temperatures is circulated through the cooling jacket of a prime mover and through a steam separating chamber having normally therein a liquid zone and a steam zone, the improvement which resides in providing a conduit having one of its ends in communication with the water zone and the other one of its ends in communication with thermostatically operated means, said'thermostatically operated means being operated upon presence of steam in the conduit, said thermostatically operated means comprising an electric switch connected to control the operation of said prime mover.

13. In a system of the character described in which water at substantially boiling temperatures is circulated through the cooling jacket of a prime mover and through a steam-separating chamber having normally therein a liquid zone and a steam zone, the improvement which resides in providing a conduit having one of its ends in communication with thewater zone and the other one of its ends in communication with thermostatically-operated means, said thermostaticallyoperated means being operated upon presence of steam in the conduit, said thermostatically-operated means comprising means operative to control the operation of said prime mover.

HANS A. B-oHUsLAv.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

